FREMONT (CBS SF / CNN) -- A federal safety regulator demanded last fall that Tesla stop claiming the Model 3 is the safest car ever tested. But Tesla has stood by the claim.
Tesla says Model 3 occupants have "the lowest probability of injury of all cars the safety agency has ever tested." The claim is still on the company's website. But in a cease-and-desist letter dated October 17, 2018, the National Highway Traffic Safety Administration's chief counsel wrote to Tesla CEO Elon Musk, saying it "is impossible to say based on the frontal crash results or overall vehicle scores whether the Model 3 is safer than other 5-Star rated vehicles."
The letter came to light this week after an exchange of letters and emails between NHTSA and Tesla executives starting last October and running through February of this year was posted on Plainsight, a legal transparency website. The documents were released under a Freedom of Information Act request. It was first reported by Bloomberg.
NHTSA's letter said this wasn't the first time Tesla has violated agency guidelines for using the federal crash test data in marketing or advertising. The regulator said it was referring Tesla to the Federal Trade Commission's Bureau of Consumer Protection to investigate whether the company had engaged in unfair or deceptive acts.
It is not clear from the documents if NHTSA or the FTC are pursuing action against Tesla at this time.
Tesla sent a response to that letter on October 31, 2018, standing by its analysis of NHTSA data.
"Tesla's statements are neither untrue nor misleading," said the letter sent to NHTSA from Tesla deputy general counsel Al Prescott. "To the contrary, Tesla has provided consumers with fair and objective information to compare the relative safety of vehicles having 5-star overall ratings."
The automaker says that 40% of cars now have 5-star safety ratings from NHTSA, so "it is more important than ever to help consumers differentiate."
A Tesla spokesman had no comment on Wednesday, and referred to the company's letter to NHTSA as its position on the matter. NHTSA did not respond to a request for comment Wednesday morning, and a spokesperson for the FTC declined to comment.
The initial letter from NHTSA came just after the Securities and Exchange Commission and Tesla had reached a settlement over charges that Musk had deceived investors when he had tweeted in August that he had "funding secured" to take the company private. Tesla and Musk each agreed to pay $20 million to settle that dispute, and the SEC dropped its demand that Musk be removed as CEO.
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